Abrading and blackboard cleaning machine



Nov. 7, 1939.

H. A. SWAN ABRADING AND `BLACKBOARD CLEANING MACHINE Filed Feb. 2, 19382 Sheets-Sheet l INVEr-OR. Hro/a A Wa/z M @UWM/WMV ATTORNEY.

Nov. 7, 1939. H` A. SWAN 2,178,865

ABRADING AND BLACKBOARD CLEANING MACHINE Filed Feb. 2, 1Q38 2Sheets-Sheet 2` BY MMVI/V ATTORNEY.

Patented Nov.`7, 1939 gUNITEID s'rATi-:s PATENT OFFICE ABRADING ANDBLACKBOARD CLEANING MACHINE Harold A. Swan, Coronado, Calif. y

Application February 2, 1938, Serial No. 188,294 s claims. (c1. S14-11o)My invention relates to a machine for abrading purposes for surfacingoors or other surfaces and for cleaning blackboards or the like and theobjects of my invention are:

First, to provide a machine of this class with a large area contactsurface in accordance with the size of the machine;

Second, to provide a machine of this class in which the action of anabrasivel belt is very emcient;`

Third, to provide a machine of this class in which the tension of thebelt is easily adjusted;

Y Fourth, to provide a machine of this class in which the drivingpulleys for the abrasive belt arein direct operative relation with theoperating motor;

Fifth, to provide a machine of this class with means for picking up thewaste material and dust vfrom the abrasive belt:

Sixth, to provide a machine of this class with means for keeping themotor cool;

Seventh, to provide a machine of this class which is very compact,light, and efficient;

Eighth, to provide a machine of this class which is easy to operate; and

Ninth, to provide a machine of this class which is very simple ofconstruction in accordance with its eiciency.

With these and other objects in view as will appear hereinafter, myinvention consists of certain novel features of construction,combination and arrangement of parts and portions as will be hereinafterdescribed in detail and particularly set forth in the appended claims,reference 'being had to the accompanying drawings and to the charactersof reference thereon which form a part of this application in which:

Figure 1 is a top or plan view of my machine in complete form ready foruse and showing a portion broken away and in section to facilitate theillustratiomFig. 2 is a side elevational view of the machine complete;Fig. 3 is a longitudinal sectional view taken from the line 3- 3 of Fig.l;

Fig. 4 is a transverse sectional view taken from the line 4--4 of Fig.3; and Fig. 5 is a partial sectional and elevational view taken from theline 5--5 of Fig. 3.

Similar characters of reference refer to similar parts and portionsthroughout the several views of the drawings:

The main casing I, operating handle 2, 'guide handle 3, motor 4, motormain shaft 5, worm pinion B, worm gear 1, drive pulleys 8 and 9,auxiliary pulleys III and II, drive belts I2 and I3, abrasive belt Il,front pulleys I5 and IB, casing side to form a base with a wide atsurface at 'from the machine outwardly for conducting it away from themachine. It, is also provided with member I1, spring 'plate I8, springplate adjust-,ment members I9, spring plate latch 20, fans 2|, switch22, electric conductor 23, intermediate casing 24, and bearing casing 25constitute the principal parts and portions of my abrading and 5blackboard cleaning machine.

` The main casing I is provided with a hollow cylindrical portion Iawhich is provided with outwardly extending anged portions Ib at itslower 10 the lower side. Mounted in this cylindrical portion Ia is themotor eld 4a with the motor armature 4b positioned therein in theconventional manner. 'Ihe motor 4 is provided with a main shaft 5 whichextends backwardly from saidmotor and secured on this shaft 5 in closeproximity to the motor is a fan 2l which is a double fan provided withblade portions 2 Ia which are relatively wide and adapted lto carry thedust and debris fan blade portions 2 Ib which serve for circulating airaround the motor for keeping it cool, and the side wall of the casingmember Ia is provided with an opening Ic for exit of the air from thefan blade portions 2lb. The blades 2Ia and 2 Ib are separated by meansof the web 2Ic which extends around a fan thus providing two sepa-` ratefan portions and the casing is provided with a seal 2 Id so that thereis provided a substantial seal in the casing by means of the web 2Ic andthe shield 2id. The shaft 5 is reduced in diameter backwardly from thefan hub Zle and is supported in ball bearing 5a which is supported in acentral portion. Id of the casing I. This shaft 5 extends backwardlysome distance and mounted on the end thereof is a worm pinion 6 whichintermeshes with a worm gear 1 shown best in Figs. 3 and 4 of thedrawings. This worm gear I is provided with oppositely disposed shafts1a which are mounted in roller bearings 1b, which roller bearings arepositioned in housings 1c which are supported by means of the maincasingl Id and the intermediate casing 24 as shown best in Figs. 3 and 4of the drawings. Secured on the 45 extended ends of the shaft 1a are thedrive pulleys 8 and 9 which are provided with relatively wide flangeswhich extend toward each other leaving a space between them at theirinner edges which is substantially lled by means in the intermediatecasing 24 shown best in Fig. 4 of the drawings. Positioned above thepulleys 8 and 9, and slightly forwardly thereof in a casing member Illcare the auxiliary pulleys I0 and II which are provided with relativelywide flange portions Illa and IIa so that they come nearly together attheir inner edges as shown best in Fig. 4 of the drawings. These pulleysI I and II are supported upon a.' shaft IIIb which is supported upon ajournal member casing Inc which supports ball bearings Id at itsopposite end which form the journal for the shaft lllb to which thepulleys I 0 and II are secured at its opposite ends.. 'I'his journalportion Ile is provided with an extended portion I0e which substantiallyfills the space between the inner edges of the pulleys I0 and II andforms a base or support for the abrasive belt at the middle portion.This journal member Inc is supported by means of a lug IIlf which issecured to a lug 24a on the casing member 24 as shown best in Fig. 4 ofthe drawings by means of a bolt I0d.

Mounted on the pulleys l and I0 is a drive belt I2. Mounted on thepulleys 9 and II is a drive 1 20 belt I 4, and positioned over these-drive belts I2 and I3 and extending over the pulleys 8 to II inclusiveand forwardly therefrom at the front and at the upper and lower sides'is an abrasive belt I4 which is wide enough to cover the full width ofthe pulleys and extend to the outer edges of the anges of said pulleysas shown best in Fig. 4.

The casing I is provided with an open mouth transverse channel If with afront wall Ig and a0 a back wall Ih which is adapted to receive the dustand waste material from the surfaces which are being surfaced, and itisdrawn therein by means of fan portion 2Ia and the dust and debris iscarried forwardly along one side Ii then insg wardly in a channel I7',then passes into the air conducting portion of the fan housing, thenupwardly and out through the opening Ik, all shown by arrows pointingthe direction of the ow of this dust and debris. Secured on the backangular portion of the all Ih of the casng I is.a handle member 2 bymeans of brackets 2a and 2b at its upper and lower sides respectively towhich the upper and lower ends of said handle are secured so that thehandle 2 is in spaced relation from the wall Ih which provides for agripfor the hand for operating the machine and shifting it from place toplace while surfacing the material to be surfaced.

Spaced slightly above th'e cylindrical portion Ia of the casing member Iis a forwardly extending casing portion Ir; and centrally on the frontend is supported a guiding handle or knob 3 which is secured by means ofa bolt 3a' on a beveled portion Im of the casing member I, thusproviding means for guiding the machine with the other hand of theoperator while it is being shifted about by means of the handle 2 withthe other hand. Extendingupwardly from the portion Ir of the casing Ibackwardly of the knob 3 is a casing portion In which i's provided witha. cover I o. Mounted on this cover I o'is a switch 22 for controllingthe circuit to the motor I from any source of electrical energy which iscarried to the machine through the electrical conductor 23, all as shownbest in Fig. 3 of the drawings.

Secured on the front end of the portion Ia of the casing I is a casingmember I1 which is provided with a substantially straight flat upperside I'Ia and secured on this flat upper surface I'Ia is a spring plateI8 which is substantially the width of-the abrasive belt Il which servesas a spring tension support for said belt which extends forwardly fromthe pulleys I0 and II over 'll the upper side of the portion la andbelow the by means of screws portion Ir of the casing member I in thespace between said member. This spring plate I8 is supported at its freelower side by means of adjustable spring members I9 which are adapted toadjust the tension and keep the abrasive belt 5 I4 in proper tension.These members I9 are provided with an adjusting hand wheel Isa tofacilitate their adjustment. This casing Il is provided with a centraljournal portion IIb in which is mounted a ball bearing vIIc which sup-10 ports Aa 4motor shaft 5b extending from the front portion of themotor I, thus providing a journal for the supporting shaft of the motorat the front end. In order to provide a thrust bearing and for taking upwear there is member I Ic which is regulated by a set screw Ildproviding proper tension on the member Ile.

Mounted over the front end of the central portion of the casing memberI1 is a spring plate A latch 20 which is Aprovided with longitudinalslots 20 20a to permit the shifting of said plate over the outwardportion of the set screw IIc. This latch member 20 is adapted to springover the outer side of the plate I 8 when the plate I8 is sprungdownwardly at its lower. sideand will hold said 2 plate inwardly forremoving or changing the abrasive belt I4. This abrasive belt I4 extendsover pulleys I 5 and I6 positioned at the lower front side of the casingI shown best in Fig. 5 of the drawings, which pulleys I5 and I6 are 30supported on shaft I5a which extends in opposite direction and thecentral portion of said shaft is journalled in the casing 25 andsupported 25a, all as shown best in Figs. 2, 3, and 5 of the drawings.

p Mounted on lthe lower side of the portion Ia of the casing member Iand the lower side of the casing member I'I is a flat felt member 26which serves as a pad for the upper side of the abrasive belt I4 tendingto hold it down into position but (n yieldable and is positioned betweenthe pulleys 8 and 9 and the front pulleys I5 and I 6.

'The operation of my abrading and blackboard cleaning machine issubstantially as follows:

An abrasiveA belt made of the proper grade of 45 sandpaper or emery'cloth, depending upon where it is to be used is made of the properlength to be placed over the three sets of pulleys and over the springplate I8. 'I'he spring plate I8 is depressed at the lower side so thatthe latch mem- 50 ber 20 extends up over the outer' side of the same forholding it inwardly; then the belt is placed in position from the openside which is normally the right hand'side of the machine; then theplate 20 is shifted downwardly and the tension 55 members I9 regulatedto give the proper tension to the abrasive belt. 'I'he electricalconductor 23 is connected with a source of lelectrical energy andthemachine vis ready for operation. By shifting the switch 22, the motorstarts which G0 causes the abrasive belt to turn over thepulleys andagainst the surface of the felt member 26 onthe lower side; the operatorwith the handle 2 in one hand and the knob 3 in the other hand can thenshift the machine over the surface to be 65 treated. Inasmuch as themachinej is small and Y light it may readily be used on verticalsurfaces such as blackboards for cleaning the same or for surfacingvertical walls or horizontal walls and the refuse is taken up in themachine and 70 passed through by reason of the fan and out through theopening Ik and may be there transferred by a hose to any place desired.

'I'hough I have shown and described a particular construction.combination, and arrangeprovided a spring '15 ment of parts andportions, I do not wish to be limited to this particular construction',combination and arrangement, but desire to include in the scope of myinventiomthe construction, combination, and arrangement substantially asset forth in the appended claims.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent is:

1. In an abrading machine of the class described, the combination of ahollow casing, a motor mounted therein with its axis longitudinallythereof, a drive shaft in connection with one end of said motorextending backwardly therefrom, a worm pinion on the extended end ofsaid drive shaft, a worm gear intermeshing with said worm pinion nearthe lower back side of one end of said casing, a shaft for said wormgear extending in opposite directions therefrom, a drive pulley securedon each end of said shaft with the surfaces of said pulleys extending tothe lower back side of said casing,pdriven pulleys in alignment withsaid drive pulleys at the upper back side of said casing, beltsconnecting said drive pulleys with said driven pulleys, and a singleabrasive belt positioned over said belts and around said casing andcontacting with said belts whereby said abrasive belt is driven by saidbelts. y

2. In an abrading machine of the class described, the combination of ahollow casing, aA

. nally thereof, a drive shaft in connection with one end of said motorextending backwardly therefrom, a worm pinion on the extended end ofsaid drive shaft, a worm gear intermeshing with said worm pinion nearthe lower back side of one end of said casing, a shaft for said wormgear extending in opposite directions therefrom, a drive pulley securedon each end of said shaft with the surfaces of said pulleys extending tothe lower back side of said casing, driven pulleys in alignment withsaid drive pulleys at the upper back side of said casing, beltsconnecting said drive pulleys with said driven pulleys, a singleabrasive belt positioned over said belts and around said casing andcontacting with said belts whereby said abrasive belt is driven by saidbelts, other pulleys coextensive with the width of said drive pulleysand said driven pulleys positioned on the lower front side of saidcasing over which said abrasive belt is supported at the front lowerside of said casing.

3. In an abrading machine of the class described, th combination of ahollow casing, a

motor mounted therein with its axis longitudinally thereof, a driveshaft in connection with one end of said motor extending backwardlytherefrom, a Worm pinion on the extended end of said 'drive shaft, aWorm gear intermeshing with said worm pinion near the lower back side ofone end of said casing, a shaft for said worm gear extending in oppositedirections therefrom, a drive pulley secured on each end of said shaftwith thesurfaces of said pulleys extending to the lower back side ofsaid casing, driven pulleys in alignment with said drive pulleys at theupper back side of said casing, belts connecting said drive pulleys withsaid driven pulleys, a single abrasive belt positioned over said beltsand around said casing and contacting with said belts whereby saidabrasive belt is driven by said belts, other pulleys coextensive withthe width of said drive pulleys and said driven pulleys positioned onthe lower front side of said casing over which said abrasive belt issupported at the Afront lower side of said casing, and a springtentherefrom, a worm pinion on-the extended end of said drive shaft, aworm gear intermeshing with said worm pinion near the lower back side ofone end of said casing, a shaft for said worm gear extending in oppositedirections therefrom, a drive pulley secured on each end of said shaftwith the surfaces of said pulleys extending to the lower back side ofsaid casing, driven pulleys in alignment with said drive pulleys at theupper backside of said casing, belts connecting said drive pulleys withsaid, driven pulleys, a single yabrasive belt positioned `over saidbelts and `around said casing and contacting with said belts wherebysaid abrasive belt is driven by said belts, other pulleys coextensivewith the width of said drive pulleys and said driven pulleys positionedon the lower front side of said casing over which said abrasivebelt issupported at the front lower side of said casing, a spring tension meansin engagement with the upper front side of said abrasive belt supportedby said casing, and means for adjusting the tension of said abrasivebelt, 5. In an abrading machine of the class described, the combinationof an elongated hollow casing, a motor mounted in the front end thereofwith its axis longitudinally of said casing, a

'shaft for said motor extending backwardly substantially centrally ofsaid casing to near the casing, a pair of drive pulleys mounted on said'shaft, one on each side of said worm gear with their surfaces extendingto the back and lower side of said casing, driven pulleys positioned'inthe upper back side of said casing in alignment -with said drivepulleys, belts connecting said pulleys, a single abrasivey belt mountedtightly on 'said belts whereby said abrasive belt is driven,

said belt extending around the outer side of said casing.

6. In an abrading machine of the class described, the combination of anelongated hollow casing, a motor mounted in the front end thereof withits axis longitudinally of said casing, a shaft for said motor extendingbackwardly substantiallycentrally of said casing to near the back endthereof, a worm pinion on the extended end of said shaft, a wormgear'intermeshing with said worm pinion, a shaft for said worm gearextending in opposite directions laterally of said casing, a pair ofdrive pulleys mounted on said shaft, one on each side of said worm gearwith their surfaces extending to the back and lower` casing, a motormounted in the front end thereof with its axis longitudinally of saidcasing, a shaft for said motor extending backwardly substantiallycentrally of said casing to near the back end thereof, a worm pinion onthe extended end of said shaft, a worm 'gearintermeshing with said wormpinion, a shaft for said worm gear ex tending in opposite directionslaterally of said casing, a pair of drive pulleys mounted on said shaft,one on each side of said worm gear with their surfaces extending to theback and lower side of said casing, driven pulleys positioned in theupper back side of said casing in alignment with said drive pulleys,belts connecting said pulleys, a single abrasive belt mounted tightly onsaid belts whereby said abrasive belt is driven, said belt extendingaround the outer side of said casing, means for supporting said abrasivebelt at the front end of said casing, said casing provided with a wastematerial conducting channel at the back side backwardly of said driveand driven pulleys.

8. In an abrading machine of the class described, the combination of anelongated hollow casing, a motor mounted in the iront end thereof withits axis longitudinally of said casing, a shaft for said motor extendingbackwardly substantially centrally of said casingto near the back endthereof, a worm pinion on the extended end of said shaft, a worm gearintermeshing' with said worin pinion, a shaft for said wo gear extendingin opposite directions laterally of said casing, a pair of drive pulleysmounted n said shaft, one on each side of said worm ge with theirsurfaces extending to the back and lower side of said casing, drivenpulleys positioned in the upper back side of said casing in alignmentwithv said drive pulleys, belts connecting said pulleys, a singleabrasive belt mounted tightly on said belts whereby said abrasive beltis driven, said belt extending around the outer side of said casing,means for supporting said abrasive belt at the front end of said casing,said casing provided with a waste material conducting channel at theback side backwardly of said drive and driven pulleys, and springtension means for supporting said abrasive beltin the upper front sideof said casing outwardly of said casing. p HAROLD A. SWAN.

